#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N = 3e5+10;
int a[N];
int n;
struct pp{
    int pos, ji, ou;
} q[N];
signed main()
{
    ios::sync_with_stdio(false), cin.tie(0), cout.tie(0) ;
    cin >> n;
    int ans = 0;
    for(int i=1;i<=n;i++)
    {
        cin >> a[i];
    }
    int dan = 0, shuang = 0;
    for(int i=n;i>=0;i--)
    {
        q[i].pos=i;
        q[i].ji=dan;
        q[i].ou = shuang;
        if(a[i]&1)
        {
            dan++;
        }
        else {
            shuang++;
        }
    }
    for (int i=1;i<n;i++)
    {
        if(a[i]&1)//奇数
        {
            ans = ans + q[i].ou+q[i].ji;
        }
        else // 偶数 
        {
            ans =ans+q[i].ji+q[i].ou;
        }
    }
    cout<<ans<<endl;
    return 0;
}   